Pokémon Mystery Dungeon: Three Explorers of Sky
by AilingStar
Summary: An amnesiac human, an earnest coward, and a prince who's supposed to be dead meet on a beach. Together, they explore dungeons.
1. Prologue

**I don't own Pokemon or Undertale.  
**

* * *

 **Prologue**

* * *

Asriel, prince of the monsters, stumbled into the throne room, scarred and beaten.

He had failed. Chara had been relying on him, and he failed her.

His Mom and Dad were standing there, saying something, but Asriel couldn't hear what they were saying.

He felt... so very tired.

"Chara... I'm sorry."

A brief flash and Asriel, prince of the monsters, no longer stood in the bed of flowers.

Toriel and Asgore watched their son fall down and turn to dust, holding their daughter's dead body in his hands. This terrible effect would have a profound impact on them, causing them to separate. One would try to kill humans to help the kingdom; the other would strive to keep the humans safe at any cost.

Meanwhile, a single flower awakened with the memories of the young prince, but only shades, glimpses., like a faded photograph. In another time, he would be the one to free monsterkind from the Underground.

In many years, after six humans had already fallen into the Underground, one final human would fall in, bringing either hope or death in their wake. Along the way, the child would meet monsters that proved to be either friends or foes.

This is not their story. For this is a story where, at just the precise moment, Asriel's essence was taken from that world and placed into another. His parents still separated, the flower still awakened with his memories, and seven children still fell down into the Underground, six of them doomed to die.

This is not that story.

This story is of the place that Asriel's essence disappeared to.

* * *

 **KRAK-A-THOOM!**

Bidoof flinched as thunder roared outside. "Whoof... can't sleep... might as well look around, yup."

Quietly, he tiptoed past Loudred and Corphish. Once he was out of the room, he breathed a sigh of relief. Waking out Loudred at this hour would be disastrous.

He turned left to explore, but before he could, he heard something from the room behind him, like something hitting the ground. "H-hello?" He asked silently.

When there was no answer, Bidoof exhaled. "Probably my imagination, yup."

Bidoof was about to sneak off to bed again, as he'd had a bit too much excitement for one night, but he shook his head. "I'd better check, just in case...

He quietly entered the room, only to freeze when he saw what was inside.

It was huge, three, maybe four feet tall, an when a flash of lightning illuminated the room...

Well, Bidoof couldn't tell what exactly it was, but it wasn't any Pokémon he had seen, and it was very badly cut.

It was a good thing that his shout woke up the whole guild, punishments be darned!

* * *

"Will he be okay? Oh my gosh, what if he's too far gone!"

"Hey, I think he's waking up! Everyone out!"

Asriel groaned as he came to. "What happened?" He muttered to himself. "Last thing I remember, I was..."

He was falling down. Struck down by the attacks of those humans. Chara had wanted him to strike back, but he refused-

Chara! He couldn't feel Chara's SOUL anywhere! Oh god, where was she where was she-

"Calm down!" A light, almost bell-like voice chimed. "You're in a very bad condition right now!"

Asriel looked up to see the voice and saw...

He didn't know how to descrribe it. "Not to be rude, but... what are you?"

The thing smiled patiently. "My name is Chimecho, and I'm a Pokémon."

"Pokémon?" Asriel hadn't heard of such a thing... at least, he didn't think so. "What's a Pokémon?"

The thing, Chimecho exhaled. "He doesn't know... was the Guildmaster right?"

"Um, excuse me? "Asriel interrupted. "Could you answer my question, please?"

Chimecho nodded. "Pokémon are... well, essentially the entire population of the – of _this_ world."

 _This_ world, Asriel noted. "You mean... I'm..."

"I'm not sure I believe it myself, but... our Guildmaster Wigglytuff thinks that you might be from another world.

Asriel laid back down. "Golly... another world..."

"Here, eat up." Some blue fruits floated toward hm... was Chimecho doing that? "Whatever you were before, you're close enough to being a Pokémon now that these Oran berries should heal you right up."

Asriel nodded and popped the berry in his mouth. Chimecho was right. He could feel his injuries healing. After Chimecho left, his thoughts started to wander. 'Chara... would you have wanted this to happen? Or would you be disappointed that I couldn't save the monsters?'

Light started to enter the room and Asriel turned to see an orb of light rising from beyond the horizon.

He'd only heard Chara, his father and Mr. Gerson talk about it a few times. 'The sun...' He smiled giddily. He'd had imaginings as to what it would be like, to see the sun, but this... This was far better than those fleeting imaginings.

'I'll find a way back home,' he vowed. 'This beauty is what monsterkind has been denied. I'm going to make it back and I'm going to free them, one way or another. And in the meantime...' He smiled as he heard voices outside the door. 'I'm going to live my life to the fullest.'

* * *

 **In the words of the one and only Wheatly... "And... There we go."**

 **This is going to be my 'quality' story. Expect updates at a Ferrothorn's pace.**

 **Don't worry, there will be some divergence, but it won't go too off the rails either. There wil be some elements from post-Gen 4, but not many. Fairy Type is about the biggest deviation there.**

 **And as always, Read and Review.**


	2. Chapter 1

**I don't own Pokémon or Undertale.**

* * *

 **Chapter 1**

* * *

"Howdy, Asriel!"

Asriel looked up. It had only been a day since he had come to this strange world, but he had already made friends with its inhabitants, including this one, Bidoof. "Yeah?"

"Chimecho said that you should be up to moving this evening," Bidoof told him. "Mind if I show you around once you're able to walk?"

Asriel smiled. "Please do!"

* * *

"Hmm..." A Shinx paced around outside the entrance to Wigglytuff's Guild. He couldn't do this. His knees were knocking, his paws were sweaty...

But... this was his dream. It had been for a long time, ever since his father had told him about the brave explorers of legend. He may have been scared, nay, terrified of the building, and he probably wouldn't be able to join, and-

"No." He expelled the doubts from his head. "My family believe in me, I refuse to be paralyzed by this any longer!" He swallowed his fear. "This is it. I have to steel my courage today."

He stepped toward the metal grate, and-

"Pokémon detected! Pokémon detected!"

"Whose footprint? Whose footprint?"

"The footprint is Shinx's! The footprint is Shinx's!"

The Shinx leapt off the plate with a shout. What the heck was that?! After glancing around, he muttered to himself, "That was too shocking... whew..."

He had failed yet again. It was a simple task in theory, but in practice... "I can't... I can't work up the courage to go in, after all... I told myself that this is the day, but..."

He reached into the bag and took out a chunk of rock. "I thought that holding on to my personal treasure would inspire me..." He put it back and sighed. "I just can't do it. They're right, I'm such a coward..." A tear escaped his eye. "This is so discouraging..." Then, without a word, he walked off, unaware of two figures behind him.

One of them spoke up. "Hey Zubat. Did you get a load of that?"

"You bet I did, Koffing." Zubat grinned wickedly.

"That little wimp that was pacing around... had something good, right?"

Zubat chuckled. "That wimp had something, that's for sure. It looked like some kind of treasure."

Koffing looked to Zubat, unaware that they had an audience. "Do we go after it?"

Zubat nodded, somehow. "We do."

* * *

Asriel and Bidoof looked at each other in shock. "Th-those two are going to be stealing that poor tyke's stone!" Bidoof started to pace. 'Oooh, what do we do... I should do something..."

"Tell Chatot or Wigglytuff," Asriel replied as he turned the crank to open the door.

"Wh-what are you doing?" Bidoof questioned.

Asriel turned to him and smiled. "I'm going to help."

* * *

"Oh wow! What a pretty sight!"

Shine could never get enough of the sight. Whenever the weather was good, the Krabby would all come out at sundown to blow bubbles. Those bubbles, catching the setting sun's rays off the waves... It was always beautiful.

It was where he went whenever he felt sorry for himself. It always made him feel good, and today was no exception. "Coming here is uplifting," He whispered to himself. "It always cheers me up."

Something to his left caught his eye. He turned to see something the same color of rust laying on the beach. "Hey... what's that? What's going on over there?"

He went over to the object, only to see that the object was a Pokémon. "Waah! Someone has collapsed on the sand!" He couldn't just stand there, he had to help!

* * *

"...happened?!" She groaned. Where was she? The last thing she remembered was... "Are you OK?"

"Ugh..." She got up and met the face of a Shinx. "Waah!"

"Aaah, sorry!" The Shinx said, backing off. "But you're awake! That's a relief!"

She looked around to see a sandy area, with bubbles floating by. 'Where... where am I...?'

"You weren't moving at all. I was really worried!" The Shinx continued. "Do you remember how you ended up unconscious out here?"

"...I was unconscious?" She whispered to herself. "What happened...?"

"Well, I'm Shine," The Shinx introduced himself. "Glad to meet you! And who are you? I've never seen you around before."

"Well..." Who _was_ she? "I think... I think I'm a human..."

"What?!" The Shinx yelped. "You say you're a human?! You look like a totally normal Vulpix to me!"

'What? No, that couldn't be true!' And yet, when she looked down, she saw not her familiar skinny hand, but a rust-colored paw. 'No...' Turning around, she spotted six orange tails. 'It can't be...' She looked into the water and, sure enough, a Vulpix was staring back at her. 'It's... it's true! I've turned into a Vulpix!'

She rubbed her head with her unfamiliar paw. 'But how did this happen?' "I don't remember anything..."

"You're.. a little odd..." Shine spoke up. "Are you pulling some kind of trick on me?"

"What?! No!" She shook her head vehemently. "I swear, I'm not lying!"

"I guess not..." Shinx replied. "Alright then, your name? What's your name?"

"Trinity," She replied without even having to think about it. "My name is Trinity."

Shine nodded. "OK. Well, you don't seem to be a bad Pokémon, at least. Sorry I doubted you, it's just..." He sighed. "More and more bad Pokémon have been turning up lately, you see! So many have grown aggressive that things have grown somewhat lawless..."

Before Shine could continue, he was tackled from behind by a shadowy figure, and a strange stone fell out of his bag. "Ouch..." He muttered.

"Shine!" Trinity rushed to his side. "Are you okay? Please say you're okay..."

"Well I do beg your pardon," one of the attackers, a Koffing, spoke up.

Trinity stumbled back as Shine turned to face the two attackers, his face almost sparking. "Hey! Why'd you do that?!"

The other attacker laughed. "Can't figure it out? We wanted to mess with you!" Zubat leered at shine. "Cant face up to us, can you?!"

Shine jumped back. "Wh-what?!"

Zubat turned towards the stone. "That's yours, isn't it?"

Shine gasped. "No! That's...!"

"Sorry kiddo. We'll take that!" Zubat swooped down, scooping the stone into a bag tied around his still-developing legs, ignoring Shine's shouts.

Koffing laughed. "Not gonna make a move to get that back? What's the matter, too scared?" He smirked as Shine flinced back. "I didn't expect that you'd be such a big coward!"

"Get back here!" The four of them turned to see a large figure running towards them.

Koffing and Zubat paled. "Time to go!" They cried, rushing into a nearby cave.

The tall figure slowed down and eventually stopped next to Trinity and Shine. "Dang it... couldn't stop them..." Despite his imposing figure, he sounded rather young.

Shine moaned. "Wh-what should I do?" The figure and Trinity looked at him. "That's my personal treasure. It means everything to me. If I lose that... No! There's no time to waste! I've got to get it back! Hey, Trinity! And, umm..."

"Asriel," The figure introduced himself.

Shine nodded. "Can I get you two to help me?"

Wait, what? "Wh-what should I do?"

"We don't have time!" Asriel interrupted. "Come on!"

Trinity nodded. "G-got it!"

R-really?" Shine beamed. "You two will really help?! Th-thank you! Let's go, quickly!"

With that, the three of them rushed into the cave.

* * *

"Alright, we have to head for the stairway," Shine spoke up, before looking at two figures nearby, a Shellder and a Kabuto. "But first, we should get rid of those enemies!"

"Are you sure they're hostile?" Asriel asked. In response, the Shellder sprayed him with water. "...Right." He punched the Shellder, sending it reeling but not quite fainting. Seeing her opportunity, Trinity snuck into the shadows of the room, then lashed out at the Shellder, causing it to faint.

"That was Faint Attack!" Shine whooped, before dashing out and striking the Kabuto, before dashing back out of range. Asriel, seeing that the thing hadn't fallen gave it a punch as well, and when that didn't quite down it, Trinity slammed into it, causing it to faint.

"Why aren't you using your moves, Asriel?" Shine tilted his head. "You do know how to use them, right?"

Asriel nodded. He had managed to get some of these weird Pokémon moves down, but... "Neither of my offensive moves would do much against the Kabuto."

Shine nodded. "Gotcha." Pointed at a nearby staircase. "The stairs are right there, let's go!"

The next two floors were much the same. They battled Shellder and Kabuto, beating them quite easily, and always found the stairs rather quickly. Asriel also took the time to grab a berry like the ones Chimecho had given him.

On the fourth floor, the group was ambushed by two Shellos. They flung mud at Trinity and Shine, and while Trinity managed to take one of them down with another Faint Attack, Shine had a bit harder time hitting the other before Asriel pounded it into submission. "And Stay down."

Shine laughed and wiped his eyes off. "Thanks, Asriel. I needed that."

"No problem." Asriel passed Shine a seed. "I think this might come in handy."

Shine nodded. "Thanks. I think it will."

They found the stairs and climbed down them, spotting Koffing and Zubat at the bottom. Shine stepped forward. "Um... Hey!"

The two turned around. "Well, well... If it isn't our old friend, the big chicken."

Asriel growled and stepped forward, but before he could do anything, Shine shouted, "Give me... Give me back what you stole from me! That's my personal treasure! It means everything to me!"

Zubat grinned. "Treasure you say? So that thing really is valuable huh?"

"It could be worth more than we'd hoped for, I'd say." Koffing chuckled. "We ought to try selling it. Who knows? It might get a good price." He gave another malicious laugh. "All the more reason not to give it back!"

Asriel facepalmed. It was a personal treasure, not a material one, how dumb could you get?

Shine gasped. "What?!"

"If you want it back that badly..." Zubat flew forward. "Come and get it! Heh-heh-heh!"

Shine acted immediately, rushing forward, striking Koffing, and falling back like he had with the Kabuto, while Asriel and Trinity both shot flames at Zubat, who screeched. "You brats!"

Before she could retort, Trinity started to cough as some purple gas went down her throat. All of a sudden, she didn't feel so good...

"That was Poison Gas!" Shine growled. "Right then..." He gulped down the seed, before exhaling a sudden burst of flame, knocking out Koffing.

Zubat blanched and flew up to the ceiling. "Hah! Can't hit me up here!"

"Hey idiot!" Asriel called, flames pooling in his hand. "You forgot, heat rises!"

With that said, Zubat soon found himself under assault from two sets of Embers, before one managed to hit him dead-on, sending him spiraling to the ground. "Ugh... we got roughed up..."

"B-blast it..." Koffing mumbled, slowly rising up. "How'd we get wiped out by wimps like them?"

Bah!" Zubat flung the bag forward, sending the stone out. "There! Take it, then!"

"Just don't think you're so awesome!" Koffing moaned. "You only won 'cause of numbers!"

"Yeah you just remember that!" Zubat shouted before the two ran away.

Shine walked forward and gingerly grabbed the stone. "Oh! It's my Relic Fragment! Am I ever glad... I actually did manage to get it back." He looked at his companions. "It's only because you two agreed to help me, Trinity and Asriel. Thank you both!"

* * *

"Thank you again, Seriously!"

The three of them had left the cave and were back on the beach. While Asriel seemed to blush at the praise, Trinity was a bit more concerned. 'I only helped because I happened to be there.. but... I guess it was the right thing to do. This Pokémon is clearly grateful. It's nice to be appreciated.'

Shine set the stone in between the three of them. "This is what they stole from me. This... is a Relic Fragment."

Asriel tilted his head. "Relic Fragment?"

Shine nodded. "At least, that's what I started calling it... But this Relic Fragment... It's my precious treasure.

"You see, I've always liked legends and lore... I always get so excited when I hear tales from the past! Don't you feel the same way?"

Asriel nodded. "Yeah, I think they're awesome!"

Shine beamed. "I thought so! Hidden troves full of treasure and strange relics..." He looked out to the sea, sparkles in his eyes. "...Uncharted territories veiled in darkness, and new lands, just waiting to be discovered! Such places must be full of unimaginable gold and treasure! And history! Wouldn't it be amazing to make historic discoveries?"

Wow. He was... very passionate.

Shine turned back to the two of them. "That's what I dream of. It's all exciting to me. So one day... I happened to come across my Relic Fragment. I admit that it looks like junk, but take a closer look."

Trinity and Asriel peered at the Relic Fragment, noticing a strange pattern on it. "See?" Shine spoke up. "That inscription forms a strange pattern, doesn't it?"

"It's true," Trinity remarked. "There is a strange inscription. I've never seen a pattern like this. Or I forgot it."

"There must be some significance to this pattern," Shine spoke up. "This Relic Fragment must be the key to legendary places! To areas where precious treasure lies! St least that's the feeling I get."

"Same," Asriel spoke up. "It feels... mystical."

Shine nodded. "That's why I want to join an exploration team. This fragment must fit into something... somewhere! I want to discover where that is. I want to solve the mystery of my Relic Fragment! So earlier, I tried joining an exploration team as an apprentice..."

Shine visibly drooped. "But... I chickened out."

"I can help."

Shine looked at Asriel "What?"

Asriel shrugged. "I know the members of the guild, I actually just came from there. I'm not a member yet, but I can talk to them for you.

"R-really?!" Shine asked, his tail flicking back and forth. "Oh, thank you so very much!" He turned to Trinity. "What about you, Trinity? What are you going to do now? You lost your memory. And you somehow transformed into a Pokémon..."

"What?!"

Oh right, Asriel didn't know. "I used to be human."

"...Okay, sure. Why not." Asriel just shook his head. "I don't know how that's possible, but... well, if you're a good person, it doesn't really matter what you are, right?"

Trinity blushed a bit. "Thanks..."

"Anyway..." Shine continued, "do you have anywhere to go and stay after this?'" No, not really. "If not, can I ask a big favor? Would you be willing to form an exploration team with me? I'm convinced that I can form an effective exploration team with you, Trinity. So will you? Please?"

Trinity started to panic. 'What should I do? I'm getting recruited out of the blue! I don't know what an exploration team is... but... It's true, I do have nowhere to go, or any clue what I should do next. I guess it wouldn't hurt to team up with Shine for now. Maybe I'll eventually discover who or what I am by hanging out with this Pokémon.' She smiled. 'OK! That's settled!'

"I'll join."

"Really? You'll form an exploration team with me?" Shine beamed.

"Hey, don't forget me!" Asriel pouted. "We beat Koffing and Zubat together!"

Shine leaped in joy. "Yes! Thank you! The three of us are going to be a great combination! Let's make this work!"

"Yeah!" Asriel and Trinity cheered.

Shine turned toward the sea. "First, we should go to Wigglytuff's place and sign up as apprentices. That's where we need to train to become a first-rate exploration team. I'm sure our training will be very tough, but let's give it our best, Trinity! Asriel!"

The three of them cheered as one, lifting their paws into the air.

* * *

 **First chapter. About time.**

 **Trust me, even though this chapter is mostly just rehashing canon, it won't all be like this. You might already be spotting divergences!**

 **Anyway, Asriel is a normal type here, but even just by leveling up he learns a lot of type coverage moves. Ember is just the beginning.**

 **And also... not all divergences will be because of Asriel.**

 **Read and Review!**


End file.
